Device for clutching reciprocable actuating rod to driven members



June 13, 1950 J. M. BLACKHALL DEVICE FOR CLUTCHING RECIPROCABLE ACTUATING ROD T0 DRIVEN MEMBERS Filed Feb. 16, 1945 INVENTOR.

Patented June 13, 1950 UNITED STATES PATENT OFFICE Original application September 29, 19513, Serial No. 504,246, now Patent No. 2,396,077, dated March 5, 1946. Divided and this application February 16, 1945 Serial No. 578,247

'7 Claims.

This application is a division of application Ser. No. 504,246, filed September 29, 1943, issued March 5, 1946, as Patent 2,396,077 and is concerned with a new clutch mechanism comprising a movable rod surrounded by a normally inoperative housing, and means for tightening around the rod a coiled spring contained in the housing, for the purpose of coupling the housing with the rod. Subsequent displacement of the rod causes displacement of the housing which has thus been coupled thereto.

The new clutch mechanism as described herein, in accordance with the disclosure of the parent application, is used in an automatic telephone switching unit of the crossbar or coordinate type, for selectively coupling tens and units actuators with associated operating members. The actuators are adapted to operate contact means for completing connections, for example, between the conductors of calling subscribers lines and the conductors of a trunk line terminating in the switching unit.

This specific use of the new clutch mechanism is chosen for explanatory purposes and is not intended to indicate any inherent limitations. The invention may be useful in connection with such devices as teletype apparatus, adding-, calculating-, check-writingand check-endorsing machines, and may also be found to be applicable in other fields Widely different from these and also from the crossbar telephone switching unit in which it has actually been employed.

Certain embodiments of the invention will be described herein with reference to the accompanying drawing. In these drawings,

Fig. 1 illustrates in front view parts of a cross-s bar switching unit showing an embodiment of the new clutch mechanism and associated parts as used in connection with 2. units actuator;

Fig. 2 is a section on lines 2--2 in Fig. 1;

Fig. 3 shows a section on lines 3- 3, Fig. 1;

Fig. 4 illustrates an embodiment of the new clutch mechanism and associated parts as used in a crossbar switching unit for controlling the selective actuation of a tens actuator;

Fig. 5 is a section taken along 5-.- 5, Fig. 4; and

Fig. 6 shows the normally inoperable clutch housing of Figs. 4 and 5, as seen from the left in F18. 4.

The crossb s i chi un t as such will be des r bed or referred to only to the ex n re: quired for an und rstan ing of the structure and opera ion of the new clutch mechanism. The previously noted patent may be consulted for further details.

Numeral 11, in Figs 1, 2 and :3. in ica th housing of 2. units housing. This actuator is made of suitable insulating material, for ex.- ample, Bakelite or nolysterin and the like, and is provided with an integral guide section 12 from which extend a number of integral pro.- jections indicated at Basil-r115. A cutout or opening I6 is provided in the housing 11, forming a recess or chamber for the reception of a coiled clutch spring 11. One end, that is, the lower end. 18, of this spring is bent at an angle as indicated at H), and the angular extension 19 is anchored in a slot in the actuator housing, as is particularly apparent from Figs. 2 and 3. The other end of the spring, indicated at 20, extends through a slot 21 in the housing to the outside thereof. The spring is normally recoiled or open, and its free end 20 is in the dot-dash line position indicated in Fig, 3. The housing of the units actuator and parts associated therewith constitute the normally inoperable element of the clutch mechanism.

The housing 11 of the actuator and the coiled spring 11 therein surround a shaft or rod 22 which constitutes the movable operating member of the structure. As described in the previously mentioned patent the rod extends vertically at one edgealongside the switching unit and may be upwardly displaced by the actuation of an armature responsive to the energization of a magnet. The displacement of the rod 22 has no effect on the units actuator so long as the free end 20 of the clutch spring 11 is in recoiled orreleased position, as show-n in dot-dash lines in Fi 3.

A number of such units actuators, for example, as described in the patent noted before, ten units actuators may be associated with the rod 22. Each units actuator corresponds in structure to the one shown in the drawings. It will be understood, therefore, that displacement of the rod 22 by its operating armature has no eifect on any of the units actuators so long as the coiled clutch springs of these actuators are all in released position. However, when the free end 20 of the clutch spring of one or the other of the units actuator is displaced into operative position, shown in full lines in Figs. 1-3, the coils of such spring tighten around the rod 22 and thus eifect a clutching action, coupling the housing ll of the corresponding units actuator with the rod 22. Subsequent displacement of the rod 22 therefore eiiects displacement of the units actuator which has been coupled thereto.

The guide portion l2 of the units actuator extends through a slot 25 in the guard member 26 which is mounted on the structural part 28 by means of its extension 21. The guard 26 is provided with a number of such slots or cutouts 25, one for each of the units actuators. Each actuator is thus axially movable to the extent of the length of its guide slot 25, but is prevented from rotating on the rod or shaft 22.

The forward edge of the guard extension 27 carries a number of cam-like projections 30, one such cam projection being provided for each of the units actuators. The free end 20 of the clutch spring of each actuator is disposed in normal position just underneath its associated cam projection 30 and to the left of the right hand edge thereof, as seen in Figs. 1 and 3. When the free end 20 of the clutch spring is moved to actuated position, as shown in full lines in Figs. 1, 2 and 3, it will be disposed in alignment with the right hand edge of its associated cam projection 30. Subsequent displacement upwardly of the coupled units actuator, by the actuation of the rod 22, also effects displacement of the spring, and the free end 20. thereof slides or rides along the right hand edge of the associated cam projection 30. The release of the clutch actuator therefore will have no efiect. The units actuator remains in its operated lifted position so long as the operating rod 22 is in such position. The cam projection 30 therefore constitutes a locking means for the structure.

. The clutch mechanism is operated by a bar 35 having an opening 36 through which extends the end 2|] of the clutch spring. Displacement of the member 35 to the right, in the direction of the arrows shown in Figs. 2 and 3, effects the tightening ofthe corresponding clutch spring by moving its free end 20 from the dot-dash position shown in Fig. 3 to that shown in full lines. The

opening 36 in the bar 35 is sufiiciently wide to permit displacement of the free end 20 of the clutch spring incident to displacement of the actuator by the rod 22. The bar 35 therefore does not interfere with the operation of the clutch housing and the clutch spring.

The rod 35 is movably mounted in an opening 31 in the support 28. In the apparatus disclosed in the previously mentioned patent a bar such as 35 is common to a plurality of switching units mounted on a base side by side. It is clear, of course, that each clutch mechanism may be provided with its individual operating member taking the place of the bar 35, and that such individual operating member may be actuated, for example, by an individual solenoid and the like, as described, for example, in the co-pending application Ser. No. 583,567, filed March 19, 1945. Suitable mechanically actuated operating means may be used if desired.

It is believed that the operation of this embodiment of the clutch mechanism will be clear from the above description. For the sake of completeness and convenience, the placement and correlation of parts as well as the sequence of operations is briefly summarized below, together with explanations as to the work performed by the units actuator when used, as assumed, in a switching unit of the crossbar type.

The rod 22 constitutes the movable operating member of the mechanism. The units actuator with its housing H and associated parts, constitutes the normally inoperative element of the structure. The housing surrounds the movable rod 22 and contains the clutch spring ll also surrounding the rod. The clutch spring in normal recoiled position has no efiect. The rod 22 can freely move up and down without displacing the housing. Any one of the actuators associated with the rod 22 may be selectively coupled by an operating member or selector bar indicated at 35. Displacement of the bar 35 tightens the clutch spring around the operating member 22 and thus effects the coupling action. Subsequent displacement of the rod 22 lifts the units actuator coupled thereto. Coincident with this operation, the free outwardly extending end 26 of the clutch spring is moved alongside the edge of the associated locking cam 3t, thus locking the clutch mechanism in operated position. The selector bar 35 can thereupon be released without afiecting the operated position of the clutch mechanism,

The Work performed by the units actuator, upon operative displacement as described above, resides in moving contact fingers Gil-fil-M associated with its projections i3l il5, respectively, into engagement with associated stationary trunk contacts 43-4445. Contact fingers iil4l l2 are each part of corresponding intermediate trunk elements extending transversely of the switching unit. Each intermediate trunk element is mounted by means of an insulating strip such as shown in part in Fig. 3 at 46. As seen in Figs. 2 and 3, the forward edge 41 of contact finger 42 is disposed underneath the associated stationary trunk contact 45. Contact fingers 4| and 4B are similarly positioned with respect to their associated trunk contacts 44 and 43.

The clutch mechanism illustrated in Figs. 4, 5 and 6 is provided in the crossbar switching unit for the selective actuation of any one of a number of tens selector bars 50. As shown in the patent noted before there are ten such tens selector bars disposed in a plane extending perpendicular to the drawing Fig. 4; that is to say, there are nine additional tens selector bars back of the bar 50 shown in Fig. 4. Each tens selector bar carries a number of projections similar to the projections l3-I4l5 of the units actuator. In the switching unit disclosed in the patent each tens actuator bar is provided with thirty such projections. One such tens actuator is associated with a sub-group of lines represented by a row of vertically superimposed sets of line and test conductors.

Each tens actuator bar 50 is provided with a clutch housing 5i. The clutch housing has a boring 52 for the reception of the lower end of a pin 53 and a recessed opening 54 forming an internal chamber in which is disposed a clutch spring 55. The lower end 56 of the clutch spring is bent at an angle and is anchored in a slot provided in the clutch housing. The arrangement is similar to that described in connection with the clutch spring of the units actuator. The upper end 51 0f the spring extends through a slot 53 in the clutch housing to the outside thereof underneath the lower edge of a locking cam 59 and then through the opening 60 in a selector bar 6|. The

and has a head 53a resting on "the armature extension. The armature '66 rotatably pivoted at 61 and is provided with a heel-piece'58 "for electromagnetic coaction with stationary heelpieces 69 of an operating magnet. Displacement incounter-clockwise direction, as seenin Fig. 4, ,of the armature 66, responsiveto the.energiza tion of the operating magnet, therefore causes upward displacement of the pin 53 associated with the clutch housing of the tens actuator rod 50. So long as the clutch spring 55 contained in the clutch housing is in recoiled position, as shown in full lines in Figs. 4 and 5, the actuation of the armature 58 and consequent lifting of the lifting pin 53 has no effect. The lower end of the lifting pin merely slides upwardly within the housing 5|. Actuation of the tens selector bar 6| to the right, as seen in Fig. 5, displaces the free end 51 of the clutch spring, thus tightening the spring around the lifting pin 53, thereby coupling the clutch housing 5| to the lifting pin. The action is similar to the clutching action of the spring described in connection with the units actuator. Subsequent actuation of the armature 56 and consequent displacement of the lifting pin 53 therefore causes operative displacement of the coupled tens actuator. The clutching action thereafter is maintained by the clutch spring. the free end 51 of which is now in engagement with the edge of the locking cam 59.

The locking cams such as '59 extend from an angular member Ill-H on which is also mounted a guide i2 having holes 13, one for each of the tens selector bars 6 I. Individual electromagnetically or mechanically operable means may be used in place of the selector bar 6| for initiating the clutching operation.

The sequence of operations of the clutch mechanism for the tens actuator is similar to the sequence of operations described in connection with the units actuator. The work performed by the tens actuator, as disclosed in the previously noted patent is mechanically similar to that performed by the units actuator, but the corresponding contact fingers of the intermediate trunk elements are operated into engagement with line and trunk conductors of subscribers lines instead of into engagement with stationary trunk contacts as in the case of the units actuator.

The joint operation of a selected tens actuator and a selected units actuator completes the connection, e. g., between the conductors of a subscribers line in a sub-group of lines with the conductors of the trunk line terminating in a switching unit.

Specific embodiments of the invention have been described and explained above merely to give examples of how the invention may be used in practice. As noted at the outset, this is not intended to indicate any inherent limitations. The invention may receive different expressions and may be used for purposes and in apparatus widely different from that briefly described herein.

Attention may also be called to certain modifications which may be made in addition to those previously mentioned. For example, the clutch springs may be made conical instead of cylindrical as shown. The clutch housings may be made of any suitable and desired material, depending on the purpose which the mechanism is intended to serve; and the spring actuating means may be directly attached to or combined with the clutch r eesieseed :19. mova ther wit Ot e m fieei eee w l Q e t t q s i e in h ,ertwh may desire to usethe invention.

It is understood, therefore, that the disclosure illustrative only, and that changes may be .meqelw tb erth se e ee s irit 9 th .fe lewi claims which define what believed to be new and desired-to have protected by United States L tt s P ent A,.c 1t h.m Qha c m sin i lone tudinally movable rod, ,a device to be operated responsive to movement of said rod, a spring adapted to operate said device and having coils surrounding said rod, clutch operating means for tightening said coils 'to causefsaid spring ,tjo gr p said rod, means for moving said rod to operate said device, and means effective in the operated position of said device to cause said spring to maintain its grip on said rod independent of said clutch operating means.

2. In a spring clutch, a housing having a longitudinal bore and a recess or opening in one wall intersecting said bore, said recess having a continuation in the form of a slot in an adjacent wall, a coiled spring located in said recess having one end anchored against an interior surface of said recess and the other end projecting from said slot, and an operating rod extending through the bore of said housing and the coils of said spring.

3. A clutch mechanism comprising a normally inoperative element, an operating member slidably disposed in said element, a spring in said element having coils surrounding said member, means for tightening said coils on said operating member to couple the element therewith, means disposed alongside said element and adapted to be operated thereby, and actuating means radially extending from said element for operating said last-named means.

4. A clutch mechanism for coaction with an axially movable operating member comprising a clutch housing, guide means for axially slidably mounting said clutch housing for displacement in a direction which parallels the axial motion of said operating member, a spring disposed in said clutch housing having coils surrounding said operating member and having one end anchored in said clutch housing and the other end projecting therefrom, a clutch-actuating member disposed adjacent said clutch housing for sliding movement relative thereto in a plane which extends at a right angle to the axis of said operating member, said clutch-actuating member coacting with the end of said spring which projects from said clutch housing, responsive to sliding movement thereof, to tighten the coils of said spring around said operating member for the purpose of operatively coupling said clutch housing to said operating member to cause displacement of said clutch housing with said operating member responsive to axial motion of such operating member.

5. The structure and combination defined in claim 4, together with means associated with said clutch housing forming a plurality of projections generally radially extending therefrom, and means ooacting with said projections and operated thereby responsive to displacement of said clutch housing with said operating member.

6. The structure and combination defined in claim 4, together with locking means for maintaining said spring in tightened position independent of said, clutch-actuating member.

'7. The structure and combination defined in UNITED STATES PATENTS claim 4, wherein a pinlike member projecting axi- Number Name ally into said clutch housing at one end thereof 846 313 Kline Man 5' 67 constitutes said operating member, means for 2 207715 Bumstead July 1 1940 generally axially moving said pinlike member to 5 2313494 Jones May 4, 1 4 move said clutch housing after such housing has 2361310 Bazley Oct 31, 94 been coupled to it by the operation of said actuating member, means adapted to be operated by FOREIGN PATENTS the movement of said clutch housing, and means Number Country Date associated with said clutch housing for effecting 10 604,383 France s Feb. 6, 1926 the displacement of said last-named means. 749,944 France May 15, 1933 JALIES M. BLACKHALL.

. REFERENCES CITED The following references are of record in the" 15 lfile of this patent: 

